The man who was diving with shark attack victim George Thomas Wainwright when he was killed said he saw his best friend's body float to the surface moments after seeing him alive.
Justin Branner was on a boat with his wife Allison off Rottnest Island on Saturday when the shark attacked the 32-year-old Texan.
Mr Branner said Mr Wainwright was his university buddy and had been a close friend for nine years.
He told Seven News last night that just before the attack their anchor became stuck on a rock and Mr Wainwright suited up to dive down to free it.
Although he did not see the attack, Mr Branner saw bubbles and then his mate's body float up. "It's something you don't want anyone to ever see," he said.
Mr Branner said being in the water was a mutual passion for the friends and they were inspired to scuba dive off Rottnest after seeing a YouTube video.
"Every chance we could get we did something on the water, that's where we spent our time," he said.
He was now concentrating on making sure his best friend's body was returned safely to the US.
"We don't want him to travel alone, so we will make sure he gets back to his family," he said.
Colin Barnett said yesterday there would be aerial shark patrols over Perth's coast daily until April 30 with patrols of South West beaches to begin in about a month.
The Premier said Surf Life Saving WA would use a helicopter to cover Mandurah to Yanchep for about four hours a day from 6.30am.
Rottnest would be included at weekends and public holidays after the attack on Saturday - WA's third shark death in seven weeks.
A second helicopter would be used by the end of next month from Bunbury to Margaret River.
Mr Barnett said there would be more frequent water patrols by lifesavers using dinghies and surf skis between 6am and 7.30am in Perth.
The increased air and sea patrols were the result of an extra $1 million from the Government.
"To have three fatal shark attacks in just the last few weeks is an unprecedented situation and it does call for urgent action," Mr Barnett said. It was important the public felt safe at WA beaches.
In Opposition in 2003, Mr Barnett called for shark patrols to begin earlier, at the start of September.
He said the patrols and their timing would be reviewed for next year.
Shadow fisheries minister Jon Ford said Labor would be flexible with the start times based on the season and demand. On a hot day before the official season, it was common sense to have patrols.